1. Field of the Invention
The present invention relates to a circuit arrangement for determining the identification of a repeater in telecommunications systems, in particular telephone systems, which, either individually, or as one of several, are permanently assigned to a specific zone of origin, individually characterized by an incoming connection line, and therefore can be used individually for the establishment of a telephone connection, depending upon the zone of origin of the calling subscriber, and a control path, used for the exchange of signals, to a translator which inter alia supplies information for the ongoing connection establishment and for the assignment of a charge pulse train can be individually switched through by means of switching elements which can be set up appropriately.
In addition, the translator having been called up, instigates the transmission of a test signal by way of a control path which has been established back to the translator in order to establish the repeater which is being used, and the test signal can be recorded, in assignment to a zone of origin, by indicating switching means which characterizes this zone for further analysis.
2. Description of the Prior Art
In particular, for the tariff assessment of international telephone connections established by automatic trunk dialing, one of the items of information which must be known in the routing control station of the so-called foreign head exchange, is the zone of origin of such a connection. From the country code which a subscriber transmits as dialed information, it will be clear that this is a connection which must be zoned in this exchange. The foreign metering pulse generator assigned to the individual trunk lines instigates connection to a central translator which must be carried out by way of a corresponding register. As soon as the register in question, which can be used during the connection establishment, has received, for example, the direction determining component of the dialed information, a request signal for the translator is formed. The request signal then supplies the register with, inter alia, the setting-up information required for the establishment of the on-going connection path. It also serves to form the information required for the charge assessment. Since the incoming trunk dialing repeaters are permanently assigned, either individually or in groups, to specific connection lines which determine the relevant zone of origin, the relevant zone of origin can be determined by interrogating the seized repeater. For this purpose, in response to an appropriate request, the translator can transmit a test signal by way of the seized register and by way of the control path which is set up to continue the relevant repeater. From here, this pulse passes to a receiving circuit which is permanently assigned to every possible zone of origin and is contained in the translator. The assigned zone of origin becomes known when one of the received circuits responds. It will be likely that, on account of the spatial arrangement of the repeaters and the translator within the relevant exchange, the test circuit will include a long system cable section. This involves the danger that mis-analysis will occur as a result of input-coupled interference pulses in the order of magnitude of the useful test pulse. A faulty statement can also occur if, due to faulty contact of individual test wires, a receiving circuit other than that assigned to the seized repeater responds. The influence of lines could also result in a fed-in test signal changing in amplitude in such a way that the receiving circuit no longer responds.